At 30 June 2009, the estimated resident population of South Australia (SA) was 1.62 million people which represented 7.4% of the total Australian population. The population increased by 19,600 people since June 2008 mainly due to net overseas migration. The state growth rate for 2008-09 was 1.2%, slightly higher than the average annual growth rate of 1.1% for the five years to June 2009. In 2008-09, SA had the second slowest state growth rate, behind Tasmania.

At June 2009, the population of the Adelaide SD was 1.19 million which represented 73% of the total state population. In 2008-09, the population increased by 14,900 people or 1.3%, a rate slightly higher than the five year annual average to 2009 of 1.0%. The remainder of the state grew by 4,700 people or 1.1%.

In 2008-09, the six LGAs with the largest population increases were all located within the Adelaide SD. Salisbury (C), located in the city's north, recorded the largest increase (2,500 people) followed by southern Onkaparinga (C) (2,300). Playford (C), which adjoins Salisbury, increased by 2,100 and Port Adelaide Enfield (C) increased by 1,500. These LGAs accounted for over half of the population increase in the metropolitan area.

The fastest growing LGA within Adelaide SD was Playford (C) which increased by 2.8% to 77,500 people. This LGA experienced a recent increase in growth as indicated by the difference between the 2008-09 growth rate (2.8%) and the five year annual average (1.9%). Conversely, the growth in inner-city Adelaide (C) markedly slowed from the five year annual average of 4.3% to 2.4% in 2008-09. North-eastern Gawler (T) grew by 2.3%, while Salisbury (C) grew by 1.9%.

The LGA of Tea Tree Gully (C) increased by 230 people to attain the population milestone of 100,000. No LGAs within Adelaide declined in population.

Outer Adelaide SD

In 2008-09, the Outer Adelaide SD recorded the highest growth rate of all SDs in the state, increasing by 1.9% (or 2,500 people). The fastest-growing LGA in this SD was Victor Harbor (C) which grew by 2.7%, followed by Light (RegC) (2.5%), located in the Barossa Valley to the north of Adelaide. Alexandrina (DC) on the Fleurieu Peninsula and Mount Barker (DC) in the eastern Mt Lofty Ranges both grew by 2.4%. These four LGAs have been among the fastest-growing in the state for several years as indicated by their average annual growth rates which ranged from 2.5% to 2.8% for the five years to June 2009.

Mount Barker (DC) had the largest population increase in Outer Adelaide (up by 700 people), followed by Alexandrina (540). The populations of Victor Harbor (C), Light (RegC) and Barossa (DC) increased by 360, 340 and 330 respectively.

No LGAs within Outer Adelaide recorded population decline although population levels in Adelaide Hills (DC) and Mallala (DC) remained stable.

In the 12 months to June 2009, the remainder of SA generally experienced smaller population increases than the Adelaide and Outer Adelaide SDs. While Yorke and Lower North SD recorded a growth rate (1.4%) above that of the Adelaide SD (1.3%), this high growth was largely attributable to the LGA of Copper Coast (DC). Located on the upper Yorke Peninsula, Copper Coast (DC) recorded the fastest growth rate in the state (3.2%). The region has recently undergone major housing and recreational developments including a marina redevelopment at Wallaroo and a golf course resort at Port Hughes. Other LGAs to record fast growth were Lower Eyre Peninsula (DC) and Tumby Bay (DC), which both grew by 1.8%.

Copper Coast (DC) also recorded the largest population increase (400 people) for a LGA outside of the Adelaide and Outer Adelaide SDs. Murray Bridge (DC), in the Murray River region, and Mount Gambier (C), in the state's far south-east, grew by 290 and 280 respectively.

Population decline

Over one-quarter of LGAs in the remainder of SA decreased in population, however, none decreased by more than 50 people. These LGAs have generally been affected by drought or record low river inflows in recent years. The largest decline was in the Riverland LGA of Berri and Barmera (DC), which decreased by 50 people. Other LGAs to experience population declines in 2008-09 were Flinders Ranges (DC) (down 40 people), Peterborough (DC) and Coober Pedy (DC) (both down 30 people) all in the Northern SD as well as Loxton Waikerie (DC), also down 30 people.

The population density of SA at June 2009 was 1.6 people per square kilometre (sq km). Most of the state had a very low population density, with 28 SLAs (comprising 92% of the state's total area) having less than one person per sq km. While the population density of SA was the third lowest of all states and territories, Adelaide SD had the highest of all the capital city SDs at 650 people per sq km.

The most densely populated SLAs within Adelaide SD were Unley (C) - East which adjoins Adelaide (C) and Holdfast Bay (C) - North (both 2,900 people per sq km), followed by Prospect (C) (2,700).

The SLAs in Adelaide SD with the largest increases in density between June 2008 and June 2009 were Playford (C) - East Central (up 50 people per sq km), Campbelltown (C) - West (40) and Charles Sturt (C) - North East (30).